Electric switch



R. 0. W. LUNDIN.

ELECTRIC SWITCH.

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1 ,370,138; Panted Mar. 1, 1921.

ELECTRIC SWITCH.

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aS E U V ME m w UNITED STATES PATENT oFF-ics.

RAGNAI O. W. LUNDIN, OF NORTH ATTLEBORO, MASSACHUSETTS, ASSIGNOB TO BARBER ELECTRIC MANUFACTURING COMPANY, F NORTH ATTLEBORO, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS. A

ELECTRIC SWITCH.

A Specification of Letters Patent.

Patented Mar. 1, 1921.

Application nica apra 1v, 191s. seal No. 290,671.

To all whom 'it may concern:

Be it known that I, RAoNAi O. lV. LUN- niN, a citizen of the United States, and resident of North Attleboro, in the county of Bristol and State of Massachusetts, have '-invented certain new and useful Improvements in Electric Switches, of which the following is a specification.

The present invention relates to switches V 7of a type generally used for household service and in which the switch elements` circuit terminals and fuses are inclosed within a covered box-like casing. The switch is operated by means of an external handle and provision is made to prevent improper operation of said handle to throw the switch into the on position, when the lid, covering the switch box, is opened to obtain access to the switch and fuses.

The present invention may generally be described and compared to show similarity to known types of switches in that the presenti` .construction includes a covered box member, containing the electric circuit terminalsswitch and fuses, and switch operating means arranged to coperate with a. lid covering .the box, in a manner that before the lid can be opened, the switch will have to be operated to break the electric circuit,

and vice versa, before the switch can be o erated to complete the circuit, the said lid must be moved into the closed position.

The object of the invention, among other things, is to produce a serviceable apparatus of a simple improved design, constructed with theminimum number of easily assembled parts, without lessening the eiliciency of .the apparatus.

An embodiment of the invention will be 4`0 particularly described hereinafter with re'ference to the .w-liaa'ein Figure 1 is a perspective view of a comaccmpanying drawings Y plete apparatus showing the switch operatf t5 ingrhan le in the oit position;

ig. 2 is a plan view showing the lid removed and a portion of the box broken away;A

Fig. 3 is a fra entary perspective view 50 showing the li switch, and operating handle in the relative ositions they are in when the switch is in t e oit position.

. Fig. 4 is a detail view of a segmental plate movable with the switch handle and providing a bearing and locking means for the same and also a lockiii device for the lid.

Fig. 5 is a detail view of the switch operating handle showing the aforesaid segmenta plate and said handle in various positions;

` Fig. 6 is a detail view showing the reverse side of .said segmental plate with a portion of i'switcli operating lever secured thereto, an 'e Fig. 7 illustrates a fragment of one side plate of the box having therein radius slots concentric with a central hole.

Referring now to said drawings, 1 designates the box-like casing constructed preferahl of one piece of sheet metal and having t e ends and corners thereof bent and secured together to form a rigid structure. A covering is provided for the box preferably in the form of hinged lid 2 .having the raised portion 3 of polygonal or other suitable shape to provide clearance for the travel of the switch element contained within the box. For convenience in opening and closing the lid 2, knob 4 is provided and to permit locking of the lid in the closed position perforated ears 5 and 6 are formed respectively on said lid and at one end of the box for the reception of padlocks or other permanent locking means.

The knife blade switch 7 circuit terminals 8, fixed contacts 9', and fuse plugs 9, are mounted on the insulatin base 10, and all of said arts are centaine within the box 1. The switch is manually operated by means of the external handle 11, and the offset bar lever 12, which is united in ('.operative relation with said handle 11. The free end of the lever 12 is loosely held within the hole 14 in insulated tie bar 13 betweenthe switch blades 7 so as to permit development of a determined amount of lost motion whereby spring 14', between said tie bar 13 and lever 12, is extended and thereby put under tension when the handle 11 is manipulated to open the circuit and thus a quick break action of the switch can be obtained.

The handle 11, lever 12, and se ental lookin plate 15, are united together xyx'lbolts 16 an move together as one unit on the central boss or bearing 17 of the plate 15, and

said hole 18 and through the medium of these slots, a wider bearing base is provided for the' switch operating elements and furthermore, said slots limit the movement of the switch handle in both directions of rotation. In this connection, i1 may be noted, where it is not necessary to permanently lock the switch handle, the slotted offset ear 20 of the handle and engaging slotted abutment plate 21, secured to the box, may be dispensed with.

The segmental plate 15 is provided with a pair of holes 22, which register with holes in the base 23 of the handle 11 through which latter holes the bolts 16 pass, and by these means the handle is secured in coperativc relation to the plate 15.' The flattened end 24, of the lever 12, is secured to the plate 15 by means of the bolts 16 and these bolts` thus besides providing an extended bearing and stops for the handle and other switch operating'elements, 'also serve to unite said elements.

A flange 25 is formed at one cnd of the segmental plate 15 and this flange with the sunken portion 26 of the plate l5 forms a housing for a pivotcd latch member 27. One end of this latch member is held by spring 28 in contact with the underside of the flange 25, and when in this position, any movement of the switch handle, in a clockwise direction, is prevented by en agement of the free extremity of the latch 2l, with a stop pin 29, projecting inwardlyfrom the side plate of the box the latch 27 and the pin 29 will take place so long as the lid 2 of the box is open, and consequentlyr the switch cannot then be moved in a clockwise direction to close the electric circuit.

The turned over edge 30 of the lid 2 carries an inwardly projecting trip pin 31 which will register with and enter the open slot 32 formed in the edge of the side plate of the box, when the lid is closed. The pin 31 will then also enter slot 32 in flange 25 and de- Eress the latch 27 into the position shown by roken lines in Fig. 5, and iii this position of the latch, the latch will be released from engagement with the nin 29 and then the switch handle and cooperating parts, may be moved into the position, also shown by broken lines in Fig. 5. In the latter position of the aforesaid parts the movable contacts 7 of the switch will be in contact with the fixed contacts 9 and the electric circuit is then closed.

It will be understood the switch handle 11 can be operated at any time to break the electric circuit, but when the switch and cooperating parts are in the position to close the circuit, the lid 2 cannot be o ened cause the gin 31, carried by the id 2, hes under the ange 25, and until the segmental plate 15 is moved in an anti-clockwise direc- 1. The. engagement of.

tion, to such an extent thatthe switch' is thrown to break the circuit and the slot 32 again registers with the pin 31, the lid cannot be opened.

The impossibility of opening the switch box when the circuit is closed and of closing the circuit ca relessly when the box is open, eliminates danger to inexperienced persons, who may for example have occasion to rcplace a blown out fuse.

Possible variations may be made from the precise embodiment of the invention herein shown and described without departing from the spirit of the invention as defined in the appended claims and I therefore do not wish to be limited to the precise detailsof the invention shown and described, butf- I claiml. In an electric switch of the class described having the switch element thereof inclosed within a covered box and operable liv external means, a lockinglmember having a latch niovably mounted ereon, said external means and locking member being united together so as to form one movable unit; and a stationary stop on said box engaging said latch whereby operation of said movable unit is prevented.

2. In an electric switch of the class described having the switch element thereof inclosed within a covered box and o erable by external means, a locking member aving a latch movably mounted thereon; said external means and locking member beingr united together so as to form one movable unit; astationary stop on said box engaging said latch whereby operation of said Aunit is prevented; a lid for said box; and a trip device on said lid en aging and releasinor said latch in the close position of said li 3. In an electric switch of the class described having the switch element thereof inclosed within a covered box and operable by external means, a locking member within said box secured to said external means .so as to form one movable unit; a latch device carried by said locking member; a fixed stop engaging said latch whereby operation of said unit is prevented a lid'for said box; a trip device on said lid enga .g and releasi id latch in the close position of said lid; and means on said locking member for'engagin said trip device whereby said lid is locke in its closed position.-

4. In an electric switch of the class described having the switch element thereof inclosed within a covered box and operable by external means; a locking member within said box united to said external means by securing devices so as to form one movable unit; and a bearing for said unit permittin only a limited partial `rotary movement ,o

defined by radius slots formed in one side of the box.

5. In an electric switch of the class described, a stationary base; a switch element mounted on said base; a lever for actuating said element; an o erating handle; an intermediate member avng a latch movably mounted thereon; means for uniting sai lever, handle and intermediatemember together so as to form thereof one movable unit; and a stationary stop engaging said latch to lock said movable unit in a determined position.

6. An electric switch com rising a switch element, an actuating lever or said element, an opera-ting handle, an intermediate member, and means roviding a common bearing and movement imiting stops for and serving to unite said lever, handle and intermediate member so that they will move as one unit.

7. An electric switch havin a switch element; a box containing said element; a composite member for operating and controlling said switch element, said composite member comprising an actuating lever and a self-contained locking member located within said box and an operating handle located without said box, and means passing through radius slots in one side of said box for uniting the com onent parts of said composite member an limiting movement thereof.

8. An electric switch having a switch element, a box containing said element; a composite member for operating and controlling said switch element; said composite member comprising an actuating lever for said switch element, an operating handle and an intermediate locking member; the latter member and said actuating lever being located within said box and the said oper- 1 ating handle being located without the box; a central bearing for said composite member carried by said vlocking member and means uniting the component parts of the composite member and also providing an extended bearing for the latter member and limiting movement thereof through engaging slots in the side of the box arranged concentrically with said central bearing.

9. An electric switch having a sw1tch element, a box containing said element; a lid for said box; a composite movable member for operating and controlling said switch element; said composite member comprisin an actuating lever connected to said switc element, a locking plate or member and an external handle; a latch device carried by said locking member; a fixed stop on said box engaging said latch when Said lid is open; and a trip device on said lid engaging and releasing said latch when said lid is in its closed position.

10. An electric switch having a switch element; a box containing said element; a lid for said box; an actuating lever for said switch element; an external handle for operating said lever; an intermediate member provided with a latch device; a stationary stop on said box engaging said latch device in the open position of said lid whereby said handle is locked against lnovement for closing the switch; a trip device on said lid engaging and leleasing said latch in the closed position of said lid; and means on said in termediate member for engaging said stationar)r slot and locking said lid in a closed position when said switch element is in the position for closing an electric circuit.

Signed at North Attleboro in .the county of Bristol and State of Massachusetts this 20th day of March A. D. 1,919.`

RAGNAT O. lV. LUNDIN. 

